This invention relates generally to an electrostatographic printer and copier, and more particularly, a cleaning system that reduces photoreceptor motion quality impact and sets a proper brush to photoreceptor interference (BPI).
A multipass IOI xerographic system requires a cleaning subsystem which is able to engage and retract from the photoreceptor. Since the cleaner must remove all untransferred toner, while not disturbing the new, pre-transferred images, the engagement motion must occur during the interdocument zone. In order to place the cleaner in a typical 50 mm interdocument zone, high engagement speeds must be used.
BPI is one of the key critical parameters in any cleaner, and is directly related to the cleaning performance. The mass of the cleaner, combined with the fast engagement speeds, causes the cleaner spacer wheels to impact the backer bars with a large transient force. This impact force disturbs image quality by effectively shaking the photoreceptor belt module with respect to the ROS. A method and/or apparatus is needed to reduce or prevent the disturbance of image quality.
Furthermore, a multipass IOI xerographic system requires a cleaning subsystem which retracts. In addition to the requirement for acceptable cleaning of toner off of the photoreceptor, the cleaner must have a low impact force on the photoreceptor belt module in order to not disturb image quality. Traditional photoreceptor backers for retracting cleaners have consisted of a single contact point to set the cleaner position as it engages. This configuration serves to decelerate the cleaner engagement motion instantaneously causing a jarring impact to the photoreceptor backer and a ringing vibration to the photoreceptor module.
The following disclosure may be relevant to various aspects of the present invention and may be briefly summarized as follows:
U.S. Pat. No. 5,597,419 to an apparatus and method for moving a cleaning brush, periodically or continuously, to avoid flat spots or voids in the cleaning brush fibers when the printing machine is in standby or off. Periodic movement of the cleaning brush or slow rotation of the cleaning brush when the machine is in a non-operational mode prevents brush "set" from occurring thus, preventing photoreceptor motion quality errors in the printing operation.
U.S. Pat. No. 5,519,480 to Thayer et al. discloses an apparatus and method for cleaning particles from a moving imaging surface. Backers are retracted from the photoreceptor to release cleaning contact between the brushes and the moving imaging surface during development of image-on-image in the multi-pass cycle. After transfer of the image, the backers move into contact with one side of the photoreceptor causing the moving imaging surface, on the other side of the photoreceptor, to contact the cleaner brushes. The brushes clean the moving imaging surface of the photoreceptor. The brushes are released from contact with the moving imaging surface when the backers are retracted, allowing the image on image multi-pass process to begin again. The brushes engage and disengage the photoreceptor in the interdocument zone (i.e. non-imaging region) of the moving surface.